Production of variable denier rayon



April 26, 1949. G. A. M. HEIM 2,468,666

PRODUCTION OFVARIABLE DENIER RAYON Filed Nov. l2, 1946 Syvum/vbo@Patented Apr. 26, 1949 UNITED STATES PATENT OFFICE PRDUCTIN F VARIABLEDENIER RAYON corporation of Delaware Application November 12, 1946,Serial No. 709,112 In Germany March 27, 1942 Section 1, Public Law 690,August 8, 1946 Patent expires March 27, 1962 8 Claims.

This invention relates to the production of rayon yarn having deniervariations and is more particularly concerned with the production ofrayon yarn having zones of low denier occurring at regular intervalsalong its length.

In the production of synthetic yarns having denier variations, it iscustomary to lengthen the filament strands of freshly spun rayon betweenthe spnnerette and the draw oi roller by periodically, sharply pushingthe yarn out of its normal path with a cam or the like. Ordinarily, thecam is driven by a mechanism entirely divorced from the extrusion ordraw 01T apparatus with the result that denier `variations which are notcorrelated with the rate of yarn travel are produced. Accordingly, theproduct produced by prior art apparatus is characterized byobjectionable lack of uniformity and its cost is increased due to thecomplexity of the apparatus used for imparting the denier variationsthereto.

It is an object of this invention to overcome the disadvantages of priorart apparatus for the production of rayon yarn having denier variationsand provide simple and inexpensive apparatus for the production ofregularly occurring thin spots in the yarn which may be used as tearpoints in the production of staple bers.

Other objects and advantages of this invention will be apparent upon theconsideration of the following detailed description in which:

Figure l is a diagrammatic view in side elevation of a single spinningposition equipped with apparatus constructed in accordance with thepresent invention for producing regularly occurring denier variations inthe yarn;

Figure 2 is a view in front elevation of the apparatus of Figure 1;

Figure 3 is a detailed View showing one position of a cam that isemployed in imparting denier variations to the yarn; and

Figure 4 is another view of the cam of Figure 3 in a diierent position.

Referring now in greater detail to the drawings, the yarn issuing from aspinnerette IIJ is led upwardly through a thread guide Il, in tangentialcontact with a pair of closely spaced rollers I2 and I3 arranged invertical alignment` over the roller I3, and under an adjacent laterallyspaced roller I4 from which the yarn is led to a draw off surface I5 ofa stepped godet I6 which includes also a larger draw off surface I'I anda sloping guide roller I8. After passage around the surface I5 of thegodet I6, the yarn is led again over the roller I4 from which it passesaround the surface I5 again, then over the guide roller I8, then aroundthe surface Il of the godet I6, then around a sheave i9, then over thesurface I1 again and finally to a point of collection or aftertreatment,not shown. A panel 20 is provided on which the rollers I2, I3 and I4, aswell as the sheave I9, are mounted.

It will also be noted that the axis of the sheave is slightlyhorizontally offset with respect to the yarn path between the rollers I2and I4. Accommodated in this offset and attached to the sheave I9 forrotation therewith, is a cam 2| provided with a sharp cam surface 22adapted to engage and displace the yarn passing between rollers I2 andI3, see Figures 3 and 4.

By the disposition of the cam adjacent the yarn path between closelyspaced rollers I2 and I3, and by driving the sheave I9 by a loop fromthe draw off godet, the cam 2I is driven by the yarn and accordingly,produces regular denier variations during the passage of the yarnbetween the rollers I2 and I3, see again Figures 3 and 4.

The location of the roller I6, spaced from, but in the same horizontalplane as the roller I3, resultsI in imparting to the yarn a very markedchange in direction in its passage between roller Ili'and the surface I5of the stepped godet I6. rihis change in direction causes the camproduced stretch to take place between the spinnerette I0 and the rollerI3 while the thread is still quite soft and deformable and prevents thestretch from being felt to any appreciable extent between the roller I3and the godet I6. It is also desirable that the cam 2| be located asnear as possible to the spinnerette I0 and that the yarn drive thesheave I9 so that the cam 2I rotates with, rather than against, thedirection of yarn travel.

What is claimed is:

l. Apparatus for the production of yarn having denier variationscomprising a spinnere'tte, a draw off device for drawing yarn from thespinnerette, means for periodically altering the length of the yarn pathbetween said spinnerette and said draw ed device to impart deniervariations to said yarn, and means directing said yarn, after the deniervariation has been imparted thereto, in driving relation to saidlength-altering means.

2. Apparatus for the production of rayon yarn having denier variationscomprising a spinnerette, a draw oif device for drawing yarn from thespinnerette, a mechanism including a cam for periodically altering thelength of the yarn path between said spinnerette and said draw oiidevice to impart denier variations to said yarn, and means directingsaid yarn, after the denier variation has been imparted thereto, indriving relation to said cam.

3. Apparatus for the production of rayon yarn having denier variationscomprising a spinnerette, a draw oil device for drawing yarn from thespinnerette, a pair of spaced rollers in the yarn path between saidspinnerette and said draw off device, yarn driven means for periodicallyaltering the length of the yarn path between said rollers to impartdenier variations to the yarn, and means directing said yarn, after thedenier variation has been imparted thereto, in driving relation to saidlength-altering means.

4. Apparatus for the production of rayon yarn having denier variationscomprising a spinnerette, a draw off device for drawing yarn from thespinnerette, a pair of spaced rollers in the yarn path between saidspinnerette and said draw oil device, a yarn driven cam for periodicallyaltering the length of the yarn path between said rollers to impartdenier variations to the yarn, and means directing said yarn, after thedenier variation has been imparted thereto, in driving relation to saidcam.

5. Apparatus for the production of rayon yarn having denier variationsat regular intervals along its length comprising a spinnerette, a rstdraw oi means, a second draw off means and rotatable means including adriving sheave for a1- tering the length of the yarn path between saidspinnerette and said first draw off means, theI driving sheave of saidrotatable means lying in the yarn path between the first and second drawoff means whereby the rotatable means is driven by the yarn at a ratecorrelated with the rate of yarn travel.

6. Apparatus for the production of rayon yarn having denier variationsat regular intervals along its length comprising a spinnerette, lrst andsecond draw off means, a pair of spaced rollers in the yarn path betweensaid spinnerette and said first draw oi means and a cam including a,driving sheave for altering the length of the yarn path between saidrollers, the driving sheave of said rotatable means lying in the yarnpath between said rst and second draw olf means whereby the cam isdriven by the yarn at a rate correlated with the rate of yarn travel.

'7. Apparatus for the production of rayon yarn having denier variationsat regular intervals along its length comprising a spinnerette, draw oimeans, a pair of vertically spaced rollers, a third roller laterallyspaced from said pair of rollers, all of said rollers lying in the yarnpath ybetween said spinnerette and said draw 01T means, said thirdroller lying close to said pair of rollers the yarn path between saidpair and said draw @ii device, and yarn driven means for periodicallyaltering the length of the yarn path between the rollers of said pair.

8. Apparatus for the production of rayon yarn having denier variationsat regular intervals along its length comprising a spinnerette, rst andsecond draw ofi' means, a pair of spaced rollers disposed verticallyabove the spinnerette in the yarn path between the spinnerette and thefirst draw off means, a third roller laterally spaced said pair ofrollers and lying in the yarn path between said pair of rollers and saidrst draw ofi" device in closely spaced relation to the former, and a camfor altering the length of the yarn path between Isaid pair of rollers,said cam having a driving sheave lying in the yarn path between saidiirst and second draw 01T means whereby the cam is driven by the yarn ata rate correlated with the rate of yarn travel.

CLEMENTINE H. H. HEIM-HOEDEMAKERS, E'xecutrir of the Estate of GustavAnton Maria Heim, Deceased.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,038,722 Dreyfus Apr. 28, 19362,098,628 Karns Nov. 9, 1937 2,133,535 Campolunghi Oct. 18, 1938 FOREIGNPATENTSI Number Country Date 325,823 Great Britain Feb. 21, 1930

